#include <REGX52.H>

void Delay1ms(unsigned int xms)		//@12.000MHz
{
	unsigned char i, j;
	while(xms!=0)
	{
	i = 2;
	j = 239;
	do
	{
		while (--j);
	} while (--i);
	xms--;
	}
}

void main()
{	
	unsigned char num=0;
	P2=~0x01;
	while(1)
	{
		if(P3_1==0)
			{
				Delay1ms(20);
				while(P3_1==0);
				Delay1ms(20);
				num++;
				if(num==8)
					num=0;
				P2=0x01<<num;
				P2=~P2;
//				P2=~(0x01<<(num++));
			}
		if(P3_0==0)
			{
				Delay1ms(20);
				while(P3_0==0);
				Delay1ms(20);
				if(num==0)
					num=8;
				if(num>0)
					num--;
				P2=~(0x01<<num);
			}
	}
}
	